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31.
Jeong MH  Kim JS  Zou Y  Yoon CS  Lim HW  Ahn J  Lee HY 《Cytotechnology》2010,62(5):461-472
This work was to investigate the effect of flavonoids from Angelica gigas Nakai on the proliferation and differentiation of PC12 cells. Several solvents including hexane, chloroform, ethyl acetate, butanol and water consecutively partitioned. We determined the ethanol crude extract of Angelica gigas Nakai. The hexane fraction was shown to contain the highest number of flavonoids as follows; 21.48 mg/g and the composition of the flavonoids was as follows: 12.24 mg/g of quercetin, 4.39 mg/g of myricetin and 2.58 mg/g of catechin. In addition, this hexane fraction greatly increased both cell growth and outgrowth of the neurite, and whose effects were three times higher than those of the other fractions. The length of the neurites was measured as ca. 110 μm in adding 50 μg/mL of the hexane fraction, which was about the same as the case of adding 50 ng/mL of NGF as a positive control. This result indicates that the differentiation of PC12 cells by the addition of the hexane fraction was comparable to the case of adding NGF. The hexane fraction was also determined to prevent apoptosis of PC12 cells by suppressing DNA fragmentation. It is interesting that the mixture of three major flavonoids, quercetin, myricetin and catechin showed stronger activity on, both PC12 cell growth and neuritis outgrowth, than when adding each flavonoid alone. We believe this was due to the synergistic effects of the three flavonoids. The activities of these flavonoids from Angelica gigas Nakai are reported for the first time in this study.  相似文献   
32.
探讨当归内酯(ASDL)对免疫抑制小鼠免疫功能的重构作用。通过小鼠腹腔注射环磷酰胺建立免疫抑制动物模型。采用免疫器官重量法和小鼠腹腔巨噬细胞吞噬鸡红细胞实验检测了ASDL对非特异性免疫功能的影响;用血清溶血素分光光度法检测了对体液免疫功能的作用;用MTT法进行了致分裂原诱导的小鼠脾淋巴细胞的增值反应实验,再用乳酸脱氢酶法测定了NK和CTL细胞活性,从而确定ASDL对小鼠细胞免疫功能的影响。结果表明:ASDL能够对免疫低下小鼠的非特性和特异性免疫功能起到一定的重构作用。但是这种效果并不是剂量依赖性的,20 mg/kg这个剂量的效果明显好于5和80 mg/kg这两个剂量。上述结果表明ASDL能够显著提高免疫低下小鼠的免疫功能。  相似文献   
33.
超临界CO_2萃取当归挥发油及其在烟草中的应用研究   总被引:2,自引:0,他引:2  
为开发新的天然烟用香料,研究了超临界CO2萃取当归挥发油的工艺,用GC/MS分析了挥发油中的挥发性和半挥发性成分,并用该挥发油进行了卷烟加香试验。结果表明:①超临界CO2萃取当归挥发油的优化工艺条件为:萃取温度40℃、萃取压力45Mpa、萃取时间1.5 h、CO2流量20 L.h-1,分离釜压力8 Mpa,分离釜温度45℃。②当归挥发油共鉴定出29种成分,主要有藁本内酯、丁烯基芙内酯、亚油酸、棕榈酸、油酸以及萜烯类化合物等。③卷烟加香评价结果表明,当归挥发油在丰富烟香、掩盖杂气、改善口感方面有较好的作用。  相似文献   
34.
Hou YZ  Zhao GR  Yang J  Yuan YJ  Zhu GG  Hiltunen R 《Life sciences》2004,75(14):1775-1786
Ligusticum chuanxiong and Angelica sinensis have been widely used in traditional Chinese medicine to treat some pathological settings such as atherosclerosis and hypertension. We determined the protective effect of the extract of Ligusticum chuanxiong and Angelica sinensis (ELCAS) on human umbilical vein endothelial cells (ECV304) damage induced by hydrogen peroxide. ECV304 cells were pre-treated with ELCAS and exposed to 5 mM hydrogen peroxide. The results show that ELCAS dose- and time-dependently protected ECV304 cells against hydrogen peroxide damage and suppressed the production of reactive oxygen species (ROS). The decrement of ROS may be associated with increased activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX). Western blot analysis revealed that ELCAS significantly increased the phosphorylation of ERK and promoted eNOS expression. These observations indicate that ELCAS protected ECV304 cells against hydrogen peroxide damage by enhancing the antioxidative ability, activating ERK and eNOS signaling pathway. Our data also provide new evidence of Ligusticum chuanxiong and Angelica sinensis in preventing both cardiovascular and cerebrovascular diseases.  相似文献   
35.
Eleven furocoumarins from Angelica silvestris and Heracleum sphondylium were tested for their antifeedant activity gainst two insect larvae: Mythimna unipuncta and the Colorado beetle Leptinotarsa decemlineata. Angular furocoumarins show a smaller effect that the corresponding linear homologues. The following order of activity is observed for substituents:
4-Methoxybenzofuran, a synthetic analogue shows also medium activity. But the most active component is a sesquiterpene: the known bisabolangelone.  相似文献   
36.
37.
White and soft calli were induced from the stemnodes of Angelica dahurica on MS medium containing lmg/L 2,4-D, and subcultured on the same medium with decreased concentration of the hormone for about half a year, until quite a number of embryogenic cell clusters were produced in calli. Protoplasts prepared only from this kind of callus were regenerable. The protoplasts-derived colonies were able to develop into embryos directly or to grow continously into calli as affected by the hormone and, in particular, by osmotic pressure in the culture medium. The embryos either formed directly or via callus stage were all capable of regenerating complete plants under proper culture conditions.  相似文献   
38.
39.
Angelica dahurica is an important Chinese herbal medicine plant, and its rhizome is of high medicinal value. In recent years, a severe decline in yield has been observed in Bozhou City (China's largest A. dahurica producing area), Anhui province, China. It showed symptoms of decline, stunting, yellowing and many galls in the roots, which was the characterization of infestation by root‐knot nematodes. A survey of root‐knot nematodes on its roots was conducted in this area from June to September, 2011. Based on our results, the nematode species on A. dahurica was identified as Meloidogyne arenaria by the morphological, biochemical and molecular methods. To our knowledge, this is the first report of M. arenaria on A. dahurica in China.  相似文献   
40.
采用高效液相色谱法建立了白芷水提液指纹图谱,色谱柱为Lichrospher 5-C18 (250 mm×4.6 mm,5μm),以甲醇-水为流动相进行二元梯度洗脱,柱温30℃,流速为1 mL/min,检测波长为254 nm.对12批不同产地的白芷药材进行了检测,共发现13个共有色谱峰,各色谱峰分离情况良好.精密度、重复性和稳定性试验中各共有峰相对保留时间和相对峰面积的RSD均小于3%,符合指纹图谱要求.该方法简便、可靠,精密度、稳定性和重复性良好,可用于白芷药材的质量评价.  相似文献   
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